Use lint version 8.1.0 to fix erroneous warning about forEach (#3903)

Android lint was erroneously warning that the forEach construct in
Kotlin required API 24+, which is incorrect, see
https://issuetracker.google.com/issues/185418482.

Work around that by forcing the Android lint version to 8.1.0.

This triggered some additional checks, which have been ignored, and a
new baseline.

app/lint.xml

@@ -33,6 +33,12 @@
     <!-- Logs are stripped in release builds. -->
     <issue id="LogConditional" severity="ignore" />
 
+    <!-- Newer dependencies are handled by Renovate, and don't need a warning -->
+    <issue id="GradleDependency" severity="ignore" />
+
+    <!-- Typographical quotes are not something we care about at the moment -->
+    <issue id="TypographyQuotes" severity="ignore" />
+
     <!-- Ensure we are warned about errors in the baseline -->
     <issue id="LintBaseline" severity="warning" />
 

gradle.properties

@@ -12,3 +12,6 @@ kotlin.incremental.useClasspathSnapshot=true
 android.defaults.buildfeatures.resvalues=false
 android.defaults.buildfeatures.shaders=false
 android.useAndroidX=true
+
+# Upgrade lint to a newer version to work around https://issuetracker.google.com/issues/185418482.
+android.experimental.lint.version=8.1.0